Superabundant: A Celebration of Pattern, Turner Contemporary, Margate

When Turner was sent to school in 1780s Margate, he found a town of knapped flint and broad horizons. Tracey Emin, two centuries later, saw a different place – a post-war sink estate for London's dregs, an East End slum-by-sea.

So Margate's shut-down Marks & Spencer seems an unpromising site for the showing of art, particularly an exhibition called Superabundant. It is an irony not lost on the show's curators. When Turner Contemporary's glitzy new galleries open in 2011, it is hoped they will do for the town what the Guggenheim has done for Bilbao. Until then, though (and like most of Margate), the homeless arts body is living hand to mouth. Rather than hide this truth, the Turner has chosen to celebrate it. In the face of all that is socially ugly, it has staged a show about prettiness.

Pattern has a vexed history in art since Ruskin, he having had unkind things to say about irrelevant decoration. All the work by the nine artists in this show is decorative, although whether it is irrelevant is another matter. Paul Moss's five-panel Danger Paintings look Riley-ishly Op, but their wavering red-and-white stripes are made of the same hazard-warning tape as flaps from the scaffolding outside the shop. The coloured squares of Richard Woods's façade piece, re-brand, echo the For Sale signs that dot Margate's blighted high street. Jacob Dahlgren's baked-bean-can sculpture, From Art to Life to Art, and his red, white and blue take on the Yellow Brick Road, Heaven Is a Place on Earth – its paving stones are Ikea bathroom scales – raise difficult questions about consumerism and consumption.

Where better to ask these questions than in an abandoned M&S; when better to ask them than now? All of which is to say that while the artists in Superabundant may have chosen to work with pattern, they have not done so wilfully. This is abstraction with a social conscience, prettiness with intent. At its most remorseless, the work in this show owns up to the fact that art is itself a commodity – that the reason it looks at home in its new commercial setting is that it is, at heart, commercial.

Thus Wim Delvoye's misnamed Marble Floor is actually made of sliced meat, Cosmati in salami. All art, it says, is only ever consumable, even the most ancient and sacred. And Lesley Halliwell's mad Spirograph pictures look like the product of slave labour which, in a sense, they are. Fanatic, 4500 Minutes is so called because it is fanatical and took 4,500 minutes to do. That's 75 hours crouched over a piece of paper, making patterns with plastic cogs. If Halliwell worked in a sweatshop, her employers would be jailed, and yet Fanatic, 4500 Minutes just looks so pretty. It makes you think, and it's meant to.

Turner Contemporary, Margate (01843 280261) to 22 Mar